1. Field of the Invention
The present invention relates to an article of footwear, such as a high boot, having a lace-tightening device adapted to adjust the front portion thereof on the user""s forefoot and instep.
2. Description of Background and Relevant Information
Footwear articles of the aforementioned type, such as the boots described in the patents DE 18 93 010, IT 19700/83, FR 1 568 397, and EP 629 793 have lace-tightening devices that close either in a conventional manner by a knot, or by means of a locking mechanism or a tensioning lever. Furthermore, depending on the possible needs to differentiate tightening, these tightening devices adjust the boot upper simultaneously on the user""s foot and lower leg, as is the case in the boots disclosed in patents IT 19700/83 and FR 1 568 397, or solely on the foot, as is the case in the boot disclosed in patent DE 18 93 010 and patent application EP 629 793. In these latter boots, a supplemental tightening device specific to the lower leg is then provided. These various ways of using the lace or cable tightening devices make it possible to adjust the fitting room to the user""s foot relatively well. Conversely, they require that a relatively substantial tensile force be exerted on the strands of the lace to obtain an efficient tightening at the instep. Indeed, due to the fact that the strands are alternately crossed, by means of eyelets, in the transverse direction relative to the boot, whereas the pulling action performed on their free ends is directed in the longitudinal direction of the boot, substantial friction occurs on the eyelets, especially on those located at the instep, and which must be overcome to bring the edges of the upper closer together on the foot. Of course, friction also occurs in the area where the strands of the lace are guided and returned in the locking mechanism, when such a blocking mechanism is used, as is the case in the boots of the documents EP 629 793 and IT 19700/83.
In the example of the boot of the document FR 1 568 397, the problem of friction and the tensile force to be produced, as mentioned hereinabove, is practically resolved due to a xe2x80x9cBowdenxe2x80x9d tightening system using a single sheathed cable pulled by a tensioning lever. However, such a system has the disadvantage of requiring the use of numerous rigid parts, whether for fixing the sheath, anchoring the cable, or mounting the tensioning lever on one of the flaps of the upper located in the zone corresponding to the user""s lower leg. Moreover, the xe2x80x9cBowdenxe2x80x9d tightening system taught connects the edges of the upper to be adjusted on the foot only in three points, and therefore does not make it possible to ensure a good distribution of the tightening between the forefoot, instep and lower leg. Furthermore, if it is necessary to free the foot or the lower leg only, this system proves ill-adapted, because it is the entire boot that is loosened. Of course, this disadvantage is also present in the boot of the document IT 19700/83, because the crossed lacing extends continuously from the forefoot to the lower leg.
Finally, a disadvantage common to all the boots and other footwear articles having a crossed lacing that rises up to the lower leg relates to the difficulty of providing room for the foot in the flexion fold zone for its insertion in or removal from the boot. In fact, in these boots, it is practically always necessary to loosen the strands of the lace by hand, at least up to the instep. This disadvantage does not affect the boots with differentiated tightening using two distinct tightening systems between the foot and the lower leg, as taught by the document EP 629 793. Conversely, the fact that the fastener of the strands of the lace is located at the flexion fold, and especially if it is a locking mechanism, poses another disadvantage. Indeed, in this arrangement, the fastener is capable of hindering the bending of the portion of the upper that surrounds the lower leg with respect to that which surrounds the foot.
It is an object of the invention to overcome the aforementioned various disadvantages of the boots and other footwear articles, including the inner liners of the so-called xe2x80x9cshellxe2x80x9d boots, having a lace-tightening device.
To this end, in the high boot according to the invention having a lace-tightening device on its bottom portion that surrounds the foot, the strands of the lace are alternately crossed by means of returns, from one edge to the other of the upper to be adjusted on the foot, from the forefoot up to the instep, and which overlaps a tongue that extends between the edges that are defined by a front opening of the upper and are then directed so as to converge up to a rigid guiding double tunnel oriented in the longitudinal axis of the boot, and with which the tongue is equipped at its top, or upper, portion beyond the flexion fold, the strands extending through the guiding double tunnel before being fastened to one another.
Thus implemented, the lace-tightening device no longer has crossed lace strands at the flexion fold, and because the strands are converging, then guided in the double tunnel along the longitudinal axis of the boot, they are presented in a direction that coincides with that of the pulling action which the user undertakes on their free ends before fastening them.
In order not to cause the deformation of the top portion of the tongue when tightening the strands, the latter are passed lengthwise through two semi-flexible and non-deformable tubular sheaths that are each inserted, on one of the edges of the upper to be adjusted, between the last return located at the instep and the guiding double tunnel against which they take support. These sheaths thus make it possible to stretch the strands in the same manner as a xe2x80x9cBowdenxe2x80x9d tightening system, and make it possible to maintain the tongue in an upright position from which one can have very easy access to the strands of the lace.
According to one construction mode, the guiding double tunnel, the tongue, and the semi-flexible sheaths are proportioned toward the top such that the free ends of the strands of the lace extend beyond the top portion of the upper that is adapted to hold the lower leg.
This top portion of the upper can advantageously be made integral or unitary with the bottom portion of the upper that surrounds the foot, but can also be attached on the latter given that, in the two examples of construction mentioned, a tightening device, in addition to that which acts on the foot, is then implemented specifically to hold the lower leg. This device for tightening the lower leg acts on the top portion of the upper by overlapping the tongue that is provided with the semi-flexible sheaths and the double tunnel. In view of the fact that the tubular semi-flexible sheaths are practically non-deformable in the direction of their cross-section, this arrangement does not hinder and has no influence on the tightening of the foot. Indeed, the strands of the lace remain free within the sheaths. As a result, it is possible to voluntarily loosen the foot without modifying the tightening of the lower leg and vice versa.
According to certain advantageous details of construction, the tongue is connected to the edges of the upper to be brought closer together, to adjust the latter on the foot, via at least one sealing arrangement such as a flexible membrane or a sealing gusset, and the tongue is provided with at least one comfort element adapted to distribute, over a larger surface, the pressure exerted on it by the strands of the lace. This comfort element is, for example, a relatively rigid or semi-flexible plate that is attached on the tongue and/or a padding element made, for example, of microcellular material.
A preferred construction includes the provision of a foot-tightening assembly such as defined hereinabove, but mounted on flexible wings extending from a U-shaped piece, and which are then attached on the bottom portion of the boot upper which is then made with a front top opening exposing the top of the foot and adapted to these flexible wings. These wings are proportioned so as to cover at least the top of the foot, and even its flanks partially, so that their coming close together by means of the lace-tightening device, which acts on the returns that are directly connected to the edges of the upper to be adjusted, properly adapts the fitting volume to that of the user""s foot. In fact, these flexible wings serve as a mounting support for the tightening assembly and contribute to the sealing of the boot. In this example of the invention, the sealing arrangement of the tongue can be connected to these flexible wings rather than the edges of the upper.
To further facilitate the tightening and fastening of the strands of the lace upon exiting from the double tunnel, a locking mechanism adapted to the spacing of the double tunnel is slipped on the two free strands, and the ends of the latter are connected to one another via a maneuvering handle.